Manifold record material and process for making it



April 24, 1951 B. K. GREEN ET AL v MANIFOLD RECORD MATERIAL AND PROCESS FOR MAKING IT Original Filed July 31, 1948 WEB.

PAPER OR OTHER RECORD MATERIAL MANIFOLD RECORD MATERIAL FRONT SURFACE COATED PROFUSELY WITH MINUTE SOLID COLOR-REACTANT ADSORB- ENT PARTICLES HELD IN A BINDER FILM.

REAR SURFACE COATED WITH RUPTURABLE FILM PROFUSELY PROVIDED WITH EN I TRAPPED LIQUID DROPLETS OF ADSORBATE MATERIAL CONTAIN- me A SUBSTANCE GIVING A DIS- TINGTIVE COLOR WHEN ADSORBED BY THE PARTICLES ON THE FRONT SURFACE OF ANOTHER UNDERLYING SHEET HAVING A FRONT ADSORB- ENT COATING.

. INVENTORS BARRETT K. GREEN 8 ROBERT W. SANDBERG BY 45W M THEIR ATTORNEYS Pate'n ted Apr. 24, 195

UNITED STATES ATENT' OFFICE MANIFOLD RECORD MATERIAL AND PROCESS FOR MAKING IT Barrett K. Green and Robert W. Sandberg, Dayton, Ohio, assignors to The National Cash Register Company, Dayton, Ohio, a corporation of Maryland Original application July 31, 1948, Serial No. 41,756. Divided and this application September '7, 1950, Serial No. 183,534

2 Claims. (01. 28228) States application, Serial No. 41,756, filed by applicants herein, on July 31, 1948.

It is, of course, recognized that heretofore it has been possible to transfer from the back of an entry receiving sheet to an under sheet, without the use of interleaved transfer sheets like carbon paper, by simply coating the back of the receiving; sheet with a carbon transfer composition or the equivalent. Such a sheet coated on the back with ordinary carbon transfer composition smudges and dirties the under sheets or the operators hands. Moreover, being coated with colored marking materials, ordinarily of dark appearance, such sheets are notattractive.

; The novel transfer sheet which is the subject of this invention is smudge-proof and pleasing in appearance, being white on both sides or white on the receiving side and a pleasing color on the back side, as the material transferred to the under sheet causes color therein only by reason of a color reaction between the transferred material and the sensitized receiving surface, producing a distinctively colored mark on the receiving surface without changing the appearance of the back of the sheet from which such transfer is made. The. receiving surface is such that, although it is sensitized, it may be used as the sur face on which the original entry is made by writing, typing or printing.

The color reaction which causes the distinctively colored marks to appear at points of pressure on the under sheets is of the type known as an adsorption color reaction wherein a color reactant material changes color when adsorbed on a suitable adsorbent material, without the presence of any ionizing medium. 7

The reactant material which changes color is an electron donor aromatic organic compound having a double bond system which is convertible to amore highly polarized conjugated form upon taking part in an electron acceptor-donor surface chemical reaction, giving it a distinctive color, and the adsorbent material is an inorganic substancev which is an acid relative to the organic compound so as to be an electron acceptor when in adsorption contact therewith. The adsorbent material is in fine particle form to provide a large adsorbent surface area per unit area of the record material, and the organic compound is carried in a fluid so it is more readily mobile to make adsorption contact with the adsorbent.

In our co-pending application for United States Letters Patent Serial No. 38,547, filed July 13, 1948, there is disclosed a pressure sensitive record material producing color by the same type of color reaction except the record material disclosed therein was coated on one side only with the two color reactants superimposed in proximity but insulated from each other by a pressure rupturable film. Any pressure or blow on such a sheet produces color.

In the present invention the individual sheet is immune to any pressure or impact, it being necessary to bring two such sheets into superimposed relation where the back surface of one sheet rests on the'front surface of another sheet of the same material before a color reaction can be caused by pressure.

The color reactant on the sensitized receiving surface is the inorganic reactant in small solid particle form profusely dispersed in a binder coating so that the particles are available for contact by the color reactant droplets transferred from'the back of the superimposed sheet by pressure. The transfer coating is a rupturable film having profusely dispersed therein small droplets of an inert oily solvent in which the organic color reactant is dissolved, said droplets being expelled locally at points of pressure.

Therefore, it is an object of this invention to provide a sheet of record material which has on a front receiving surface a coating containing small solid particles of a first color reactant material and which has on the rear surface a pressure rupturable coating which has profusely dispersed therein minute liquid droplets containing a second color reactant which produces a distinctive color when in contact with the first color reactant, the droplets being extrudable locally from the coating on pressure being applied so as to come in contact with the receiving front surface of an underlying sheet of the same kind, there to produce a distinctively colored mark.

Another object of the invention is to provide a process for making such record material.

Further objects and objects relating to details and economies of production will definitely appear from the detailed description to follow. The objects of'this invention have been attained by the several embodiments thereof described in detail in the following specifications. The invention is clearly defined and pointed out in the appended claims.

The drawing is a schematic showing on a large scale of a portion of a piece of the novel record material.

The sheet or web used as a base for the coat ings preferably is thin paper although other materials of similar utility suitable for writing or printing may be employed.

The sensitized receiving surface of the sheet contains as the active ingredient'a material upon which the active ingredient of the liquid droplets received from the bottom of an overlying sheet may be adsorbed, the adsorbate in the liquid and the adsorbent being selected so as to produce a color upon adsorption taking place.

Among the satisfactory adsorbents from an economic and functional standpoint is attapulgite in which the natural base exchange cations have been replaced by hydrogen or cations of nickel, copper, iron, zinc, mercury, barium, lead, cadmium or potassium. Mixtures of these adsorbents may be used withgood results. All of these materials may be applied to the sheet by use of a white or colorless'binder to give a White surface which will receive ink or other marking fiuid as well as being adsorptive with respect to the adsorbate in the liquid received from the rear surface coating of an overlying sheet. Thus, the novel manifold sheet may be used as a top sheet as well as an intermediate or bottom sheet of a stack.

The color reactantadsorbate carried in the rear surface film of the novel manifold sheetis present therein dissolved in minute droplets of an I oily, non-evaporable, inert liquidmedium, preferably a chlorinated diphenyl and may consist of oneor more color reactants such as crystal violet lactone, which is 3,3 bis(p-dimethylaminophenyl) -6-'dimethylarnlino phthalide, having the structure (C H gN- N CH 1 mom malachite green lactone, which is 3,3.-bis(p-di tetrachloro malachite greenv lactone. which is, 3,3 bis(p-dimethylaminophenyl)-4@-5e6-'7 tetrachlorophthalide, having the structure and 3,3 bis(p-diethylaminophenyl)-6-dimethyl amino phthalide, having the structure 2 5) zN- N (C 2H5) 2 United States Patent No. 2,374,862 issued on May 1, 1945, which was useful only as an overlying sheet and which was not sensitized to receive data from an overlying sheet. The present improvement provides a record material sheet having the dual features of being sensitized to receive data from an overlying sheet and of transferringit to an under sheet. The novel manifold sheet is smudge-proof on both sides and is not subject to' discoloration by handling as the'reactants are on opposite sides of the-sheet.

In the following examples, there will be described embodiments of 'this invention by which the objects/of the invention-have been successfully attained.

Example 1.-The following embodiment -of this invention constitutes the best mode of applyingthe principles thereof as contemplated up to the; present time and may be considered the preferredf embodiment. It comprises a base web of paper, or the like, on one-surface of which, called the transfer surface or rear surface, acoating is applied which becomes a solid pressure-rupturable insulating film-in which are entrapped a profuse number of minute liquid droplets-inwhich a color reactant substance has been dissolved; These droplets are, on the average, ofthe order of-from- 1 to 5 microns in diameterand arespaced apart, on the average, a distance of the order of /2 micron. The preferred thickness of this coating-- forming the transfer surface; when dry;- is of the order of .001 of an inch- The transfer coating is made by dissolving one partLby weight, of animal gelatin-having an isoelectric point of pH 8 and a jelly strength" of 275 rams. as, measured by theBloom gelometer, with.

:three parts, by weight of water heated to 150 Fahrenheit.

. Into four parts, by weight, of gelatin solution there is dispersed, or emulsified, three parts, by

weight, of a solution ofcrystal violet lactone,

which is 3,3 bis(p-dimethylaminophenyl)-6-dimethylamino phthalide, mixed with an equal weight of bis(p-dimethylaminophenyl) methane, being known as methylene base and having the structure H oHom-QdONwmn The solution of crystal violet lactone and methylene base is made by dissolving 1 parts, by weight, of crystal violet lactone and 1 /2 parts,

by weight, of methylene base in 9'7 parts, by

. weight, of chlorinated diphenyl which has a chlorine content averaging 48 per cent by weight. This solution is heated to the temperature of the gelatin solution before it is added thereto and The emulsion is applied-while still hot, or if allowed to cool, after'reheating to 150 Fahrenheit, and is dried either under normal atmospheric conditions or by artificial means such as a hot air blast or on a heated drying drum such as is commonly used in paper coating machines. It

is considered that drying under normal atmospheric environment gives a somewhat better and 0.1 per cent, by weight, of a wetting agent such as dioctyl ester of sodium sulfosuccinate. The wetting should be allowed to persist for several minutes followed by a drying operation in a low humidity atmosphere, either at room temperature or at an elevated temperature as high as 180 Fahrenheit. The surface wetting may be accomplished by floating the coated paper on the water, coated side down, or by carrying it around a partially submerged drum with the coated surface facing outwardly.

Onto the front receiving surface of the sheet is coated the adsorbent color reactant material in a binder. In making the adsorbent coating, 20 per cent, by weight, of paper coating starch in water is cooked at 200 Fahrenheit for minutes and cooled to room temperature. Separately, 1 part by weight of the selected base-ax changed attapulgite is dispersed in three parts, by weight, of water, by use of a ball mill or equivalent. Four parts, by weight, of the attapulgite material dispersion is mixed with one part, by weight, of the starch solution. The resultant mixture is applied to the sheet, at room temperature, in any convenient manner, as by a paper coating machine. This adsorbent coating, when dry, should have a thickness of about .005 of an inch.

The coating thickness specified may be varied by 25 per cent, or more, without interfering with the sensitivity thereof.

This record material, in the unused state is substantiall white on both'sides and the dropof applied pressure.

lots of color reactant when expressed by pressure onto the adsorbent surface of another like sheet will produce a dark blue mark, which intensifies on standing, defining sharply the area The droplet size is so small that the mark appearing on the adsorbent surface caused by drawing a line on an overlying sheet appears as a continuous line, and not as a series of dots.

The compound crystal violet lactone may be made by the process described in United States crystal violet lactone. The color produced in the same as in Example 1.

Example 3.-Another embodiment of the invention is the use of malachite green lactone, which is 3,3 bis(p-dimethylaminophenyl) phthalide instead of the crystal violet lactone of Example 2. This provides a substantially white record material giving a green color when adsorbed on the attapulgite material but it is not as intense as the blue of crystal violet lactone.

Example 4.Another embodiment of the invention is the use of an equal weight of tetrachloro malachite green lactone, that is to say 3,3 bis(p-dimethylaminophenyl) 4,5,6,'7. tetrachloro phthalide, in place of the crystal violet lactone of Example 2. This provides a substantially White record material giving a green color reaction.

- Example 5.-Another embodiment of the invention is the use of an equal weight of 3,3 bis(p diethylaminophenyl) 6 dimethylamino phthalide, in place of the crystal'violet lactone of Example 2. This makes a substantially white record material giving a blue color reaction.

In Examples 1 to 5, inclusive, there may be substituted for the starch a mixture of starch, casein and a synthetic latex made of butadiene-styrene copolymer material. In such a binder when dried with the adsorbent particles therein, the amount of starch should be '7 per cent, the amount of casein should be 1 per cent and the amount of latex should be 7 per cent, all by weight, with respect to the weight of the adsorbent material. In making the binder containing casein and latex, a starch solution, as described in Example 1, is made and allowed to cool. Next, 1 part of casein is dispersed in two parts of cold water, by weight, and allowed to swell for one-half hour, after which seven more parts, by weight, of cold water and of a part, by weight, of ammonium hydroxide of 25 Beaum are added. This casein dispersion is heated on a water bath at Fahrenheit for 15 minutes and then allowed to cool. The latex to be used should contain approximately 45 per cent of solids in water. The adsorbent material particles to be used are dispersed in water as set out in Example 1 except the water should contain 0.2 per cent, by weight, of sodium pyrophosphate. To 10 parts, by weight, of the dispersed adsorbent, eliminating the weight of the water, is added 3.5 parts, by weight, of the starch solution, 1.6 parts, by weight, of the latex,

7d and 1 ,part, by weight, of the casein solution.

Binder {material is characterize a ry greater iadhesion to the paper and-has excellent properties as far as the access of the adsorbent particles to the-action of the liquid color reactant sweets expel-ledthereonto is concerned.

Referring to the drawing, l0 indicates the sensit'ilzed receiving surface coating containing the adsorbent colorreactant, H indicatesthe supporting Web, such as paper, and [2 indicates the transfer coating containing the liquid droplets in 'which the-adsorbate color-reactant material is dissolved.

A particular "system utilizing the novel manifold record material disclosed hereinis disclosed il'1*0l11 co-pendinjg application for U. S. Letters Patent,'-Seria1 NO. 41,757, filed July 31, 1948,

wherein a stack of such sheets in superimposed relation is provided for use in makingmultiple iiopies through a single impression.

' It is understood that the novel manifold record f niater ial described herein is susceptible of conesideriablc Variations without departing from -s'pir'it of the invention.

the

What is claimed is: 1. "A sensitized record material'adapted to be ifaceof the sheet comprising a binder containing profusejnumbers of minute solid particles of adlsorb'ent material;- and'a pressure-rupturable coating' 'on the rear transfer surface, having entrapped therein a profuse number of minute liquid droplets'containing a substance which is adsorbable on material like the adsorbent particles in the coating on the front receiving sur face-and reactant therewith-on contact to form a distinctive color, recording pressures on the front receiving surface through the adsorbent ocating: causing rupture of the coating on the rear transfer surface locally at the points of pressure there to release and eat'rude o'nthe surface of the said ruptured coating droplets of the *liduidgthere available for adsorption on the re- 8 ceiving surface of an undersheet to produce a distinctively colored mark thereon, thei ad's'orbent material being attapulgite in whichthe natural base exchange cations have beenreplaced by one of the'groulp consisting of hydrogen, nickel, copper, iron, Zihc, mercur barium, lead, cadmium and potassium, and the adsorb'able material beihg an electron donor-aromatic compound having a double bond system which is convertible to a more highly polarized conjugated form upon taking part in an electron acceptor-donor surface chemicalreaction with the adsorbent, giving it a distinctive color.

2. A process for making a sensitized record material sheet to be used in conjunction with other sheets of record material of the same kind, in superimposed relation and facedvinthe same direction to, formia manifoid pack, including the steps of coating one side ,of a sheet of material,

suitable for a manifold web, iwitha film of binder material in which is profusely dispersed minute solid particles of ail/adsorbent material which is one of two substances which comprise an .adsorbent and an adsorbate which produce color in contact; and the steplof coating the other side of the sheet with an emulsion having a continuous phase :dryable .to .a .pressure-rupturable film and having ;a discontinuous phase of an inert oily liquid containing the adsorbate substance whereby upon .=drying the discontinuous phase isentrapped in the film. asa profusionof'minute droplets of liquid whichimaybe released .locally by pressure applied Eto the 'sheet, the adsorbent material being attapulgite in which the natural base exchange cations have been replaced by one of the group consisting of hydrogen nickel, copper, iron, zinc, mercury, :barium, lead, cadmium and potassium, and the adsorbate material beingan electron donoraromatic compoundhavlng a double bond system which is convertible to a more highly polarized conjugated form upon taking .part in-an electron acceptor-donor surface chem- '-ical-reaction with the adsorbent, giving it a distin ctive color.

BARRETTFK. GREEN. ROBERT W. SANDBERG.

:No references cited. 

